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Medical Insurance Billing for Fill-In Optometrists
Locum Tenens Overview
- Locum tenens allows a substitute optometrist to provide care on behalf of a regular provider under temporary coverage arrangements.
- Claims are billed using the regular provider's NPI with the Q6 modifier to indicate a substitute clinician.
- Medicare generally permits this for up to 60 continuous days.
- Other payers may have different rules—always verify before billing.
Q6 Modifier Overview
- Used to report services provided by a substitute provider
- The regular provider's NPI remains on the claim
- Identifies the substitute provider with the Q6 modifier
- Medicare generally allows up to 60 continuous days
Q6 Modifier Recognition by Insurance Type
| Insurance Type | Q6 Recognition | Verify With |
|---|---|---|
| Traditional Medicare | Generally recognized. Billing under the regular provider's NPI may be permitted when CMS locum tenens requirements are met. | CMS |
| Traditional Medicaid | May be recognized. Some states require the fill-in doctor to be enrolled with Medicaid before services can be billed. | State Medicaid Program |
| Medicare Advantage (MA) | Often recognized. Some plans require temporary provider enrollment or provider linking. | Medicare Advantage Plan |
| Medicaid Managed Care (MCO) | May be recognized. Some plans require the fill-in doctor to be credentialed with the MCO. | MCO Provider Relations |
| Commercial PPO | Often recognized. Some carriers require the fill-in doctor to be credentialed. | Insurance Carrier |
| Commercial HMO | Less commonly recognized. The fill-in doctor may require plan approval or credentialing before services can be billed. | Insurance Carrier |
| Blue Cross Blue Shield Plans | May be recognized. Some plans require credentialing of the fill-in doctor. | BCBS Provider Services |
Educational Resource Only — Information provided by EYEneedaDOC is for general informational purposes only and should not be considered legal, billing, coding, credentialing, tax, reimbursement, or professional advice. Providers are responsible for independently verifying payer requirements before submitting claims.